The present invention relates to an artificial vision system for regenerating or restoring vision.
Recently, a study has been conducted on an artificial vision system that promotes regeneration or restoration of vision by electrically stimulating cells forming the retina with electrodes or the like placed inside the eye. As such an artificial vision system, there are a type that stimulates cells based on an image picked up outside the body (hereinafter, referred to as the external imaging type), a type that stimulates cells based on an image formed on photodiode arrays or the like placed inside the eye (hereinafter, referred to as the internal imaging type), etc.
Regarding the artificial vision system described as above, in order to supply an apparatus to be placed inside the eye with power wirelessly from outside the body, there has been discussed a method of supplying power through electromagnetic induction using a primary coil placed outside the body and a secondary coil placed inside the eye.
However, when a frequency band and magnitude of electromagnetic waves suitable for use in a human body are concerned, it is difficult to supply required power with the secondary coil having an air core, that is, having no magnetic core, and therefore a coil having a magnetic core has to be used. Nevertheless, a coil having a magnetic core is so heavy that it is not suitably placed inside the eye. Moreover, when a coil having a magnetic core is placed in the vicinity of the anterior ocular segment, incoming light from outside the eye may possibly be blocked by the magnetic core in the case of the artificial vision system of the internal imaging type.